Derive Macro SqlTemplate

#[derive(SqlTemplate)]
{
    // Attributes available to this derive:
    #[template]
    #[addtype]
    #[ignore_type]
}

Derive macro for generating type-safe SQL templates using Askama.

This macro generates boilerplate code to integrate Askama templates with SQLx queries, providing compile-time SQL validation and parameter binding.

Attributes

#[template(...)] (Required)

Defines the SQL template configuration. Accepts these parameters:

• source: Inline SQL template content (supports Askama syntax)
• ext: File extension for Askama template engine
• print: Debug output options (none|ast|code|all)
• config: Path to custom Askama configuration file

#[addtype(...)] (Optional)

Specifies additional type constraints for template variables:

• Accepts comma-separated types implementing sqlx::Type + sqlx::Encode
• Required when using non-field types in template logic

#[ignore_type] (Optional)

Marks struct fields to skip SQLx type validation:

• Use for fields that shouldn’t participate in parameter binding
• Typically used for helper fields or complex types

Example

use sqlx_askama_template::SqlTemplate;

#[derive(SqlTemplate)]
#[template(
    source = r#"
    SELECT * FROM users
    WHERE name = {{e(name)}}
    AND age > {{e(min_age)}}
    "#,
    ext = "sql"
)]
#[addtype(i32)]
struct UserQuery<'a> {
    name: &'a str,
    #[ignore_type]
    min_age: i32,
}

Generated Implementation

Implements SqlTemplate trait with these methods:

• render_sql() -> Result<(String, Arguments<DB>)>
• render_execute() -> Result<RenderExecute<DB>>

Panics

• If required source attribute is missing
• If template syntax errors are detected at compile time
• If type constraints for template variables are unsatisfied

Note

The generated code requires these dependencies in scope:

• sqlx::{Encode, Type, Arguments}
• askama::Template